Things are not looking up, sadly, on the global warming front, especially over the past fortnight. Concerns have aggravated further since East Antarctica, the coldest location on the planet, experienced an unprecedented episode of warm weather and an ice shelf the size of New York City collapsed, at the beginning of a freakish warm spell. The collapse last week, captured by satellite images, is a first in human history in the frigid region which recorded temperatures soaring more than 40 degrees Celsius than normal. The area had been shrinking rapidly the last couple of years, and now scientists wonder if they have been overestimating East Antarctica’s stability and resistance to global warming that has been melting ice rapidly on the smaller western side and the vulnerable peninsula. Ironically, the area was long thought to be stable and not hit much by climate change.
The ice shelf, about 1,200sq km wide and holding in the Conger and Glenzer glaciers from the warmer water, collapsed between March 14 and 16, according to ice scientist Catherine Walker of the Woods Hole Oceanographic Institute. She said scientists have never seen this happen in this part of the continent, making it worrisome. “The Glenzer Conger ice shelf presumably had been there for thousands of years and it’s not ever going to be there again,” said University of Minnesota ice scientist Peter Neff. Though the loss of ice is minimal, what is alarming is where it happened, both said.
The previous assumptions about East Antarctica’s stability may not be correct, Neff worries. If the water frozen in East Antarctica melted — in a millennia-long process if not longer — it would raise seas across the globe more than 160ft. It’s more than five times the ice in the more vulnerable West Antarctic Ice Sheet, where scientists have concentrated much of their research. Helen Amanda Fricker, co-director of the Scripps Polar Center at the University of California San Diego, said researchers have to spend more time looking at that part of the continent. Scientists had been seeing this particular ice shelf — closest to Australia — shrink a bit since the 1970s, Neff said. Then in 2020, the shelf’s ice loss sped up to losing about half of itself every month or so, Walker said.
The event is completely unprecedented and upended expectations about the Antarctic climate system, said Jonathan Wille, a researcher studying polar meteorology at Université Grenoble Alpes in France. “Antarctic climatology has been rewritten,” tweeted Stefano Di Battista, a researcher who has published studies on Antarctic temperatures. Such temperature anomalies would have been considered “impossible” and “unthinkable” before they actually occurred, he added.
Amid all of the variability in Antarctica, fingerprints of human-caused climate change are still evident. Its western ice sheet is losing mass while western parts of the continent and the peninsula are among the fastest-warming regions on Earth. Warm ocean temperatures threaten to destabilise Antarctica’s Thwaites Glacier, a slab the size of Florida that contributes about 4% of annual global sea level rise. The historically high temperatures in Antarctica follow a pulse of exceptional warmth on the planet’s opposite end. On March 16, temperatures near the North Pole catapulted 50 degrees above normal, close to the melting point.
However, one expert thinks that only part of East Antarctica is a concern. “Most of East Antarctica is relatively secure, relatively invulnerable and there are sectors in it that are vulnerable,” said British Antarctic Survey geophysicist Rob Larter. “The overall effect of climate change around East Antarctica is it’s chipping away at the edges of the ice sheets in some places, but it’s actually adding more snow to the middle.” The take home point is that more needs to be done to curtail global warming.
